Rubber isolation feet worsened speaker performance?

[Doodski]

In the olden days of the 1980s, we 'spiked' everything pretty much... Linn speakers *definitely* 'sounded better' with spiked stands, even into a suspended floor. BBC-Derived speakers with 'talky boxes' don't seem to change at all and my Harbeth tables/stands simply sit on a carpeted floor and are never played at a serious volume as I once did many years ago.

KEF tried decoupling their bass drivers from the enclosure and in one sense it worked, while totally destroying the perceived quality of bass. It only lasted one generation of speakers I remember...

Regarding KEF do you mean like a 107.2, 105.2 and a 104.2 speaker?

OOOPs... I now read a little further and see you meant what I suspected. I have listened to all 3 KEFs extensively and I found the bass to be OK but it was limited when cranking up the power. The sound would simply and suddenly get distorted when the woofers ran out of ooomph.

 

[Great Sun Jester]

I use these, they work great with the spikes on the speakers. I do not get these from Amazon; however, this is a very good price delivered.

Amazon.com

 

[flexy123]

So, simply spoken, in particular for front-firing sub, SPIKES = better, as the elastomer/rubber pads would make the sub "float" and it might result in sloppy bass?

 

[DSJR]

Regarding KEF do you mean like a 107.2, 105.2 and a 104.2 speaker?

OOOPs... I now read a little further and see you meant what I suspected. I have listened to all 3 KEFs extensively and I found the bass to be OK but it was limited when cranking up the power. The sound would simply and suddenly get distorted when the woofers ran out of ooomph.

Not sure that this was ever done by anybody, but as well as checking the carcass for resonances, maybe they should have played a few 12" pop-rock singles into them and checked the driver chassis itself for resonance on percussive music.

I've probably got it all wrong, looking back, as so much I thought was true isn't really, or was a distortion of provable facts, but the evidence is that KEF abandoned it shortly after, or if they continued that idea, they maybe have done much research into the whole driver-enclosure termination... Got to say (again) I love ATC's way with their bigger classic models, they have an effin' thick front baffle and the mass of the bigger stand mounted models crush carpet pile into submission with NO need for spikes, although they've joined the fashion on the 100 and 150 stand mounted models (they're so bloody massive they just wouldn't move).

These 150's were sublime in the large space they were playing in (apologies folks, wrong thread, but the pic shows the spikes - FFS!!! )

 

[NTK]

KEF tried decoupling their bass drivers from the enclosure and in one sense it worked, while totally destroying the perceived quality of bass. It only lasted one generation of speakers I remember...

No. KEF continually refines its implementation. Below is from the KEF white paper for their latest Blade and Reference Series Meta loudspeakers.

 

[DSJR]

No. KEF continually refines its implementation. Below is from the KEF white paper for their latest Blade and Reference Series Meta loudspeakers.

See my later post Thanks for posting the confirmation of what they're doing today

I worry that the forces trying to push the cone forwards, will push the magnet assembly backwards slightly. Maybe the movement isn't sufficient and I'll happily concede that what they're doing now is rather more sophisticated than three rubber grommets around the chassis fixing holes. I wonder if they've played percussive music through the Blades, recording each method as in the chart above - and then done a null test of sorts to see what if any losses there are? Not sure it's quite as cut-n-dried as they make out, but I don't know the engineers and can't ask them directly to be put straight on this.

 

[Purité Audio]

I imagine KEF may have taken the odd measurement.
Keith